At present there are well known two types of aircraft ground simulators in the world: the first one is destined for training the pilots in aircraft flight control for different flight modes and simulated situations occurring during the flight, and the second one is destined for training in pilot rescue practices for different simulated and emergency situations.
The aircraft simulator of Link (Meerovitch G. Sh. et al., Aircraft Simulators and Flight Safety, Air Transport, Moscow, p. 15, 1991) represents a simplified model of a single-seat airplane with the cabin fixed at a universal joint permitting the aircraft to perform simulated flight mission with changing angles of pitch, yaw, and roll. An instructor could be present to control the pilotage according to the given program. However, such simulators do not imitate emergency situations and training pilots in such situations.
The integrated aircraft simulator is well known (ibid., pp 28-31), which contains a cabin for the crew with cockpit panels equipped with simulators of necessary standard instruments, control system, working places for pilots, system for simulation of the outside situation, motion system, computer system, instructor and flight commander panel. The simulator is designated for training in flight procedures, flight control skills at different flight stages or in certain nonstardard situations. However, the training program for pilots does not contain imitation of emergency situations.
The virtual aircraft simulator is well known (RU, 2191432, C1), which contains in the cabin of real aircraft a working place for a training pilot, units of the objective control system and weapon control, adapter with the output connected with the input of the pilot protective helmet with the virtual glasses, through which the information is transmitted and received from the ground flight data processing unit containing the module for flight information, module for comparison of the aircraft control in real flight and in the training regime, module of configuration and flight data access, module for sensing pilotage elements, module for animation of the pilot panel and outside space, module of preflight training and testing, module of the database of calculated and registered flight data, module for control of training regimes.
The aircraft simulator is well known (RU, 2114460, C1), which contains the real aircraft with flight controls, their units and systems, sensors and automatic control system with connected sensors and power flight controls, terrain modeling units, generation units and outside situation displays, unit for data exchange with the flight control and other aircraft during formation flight; database of the training flight, signal processing unit including the device for calculation of navigational parameters, units for modeling acoustical effects, unit for simulation of the aircraft flight dynamics, unit for image formation of the instrumental panels, unit modeling operation of the aircraft systems and units.
The unified multifunctional aircraft simulator is well known (RU, 2087037, C1), which contains the computing system with program modules for realization of training scenarios, modules for objective control of a trainee and instructor, unified working places for the instructor, complex of unified working places for trainees, unit for flight information input, and database of training scenarios. The simulator calculating system imitates flight operation control, uncontrolled flight in case of control failure, presentation of flight information on the instrument panel and visualization system. Moreover, it provides the adequate artificial feel of control for the control stick, input of typical emergency situations caused by the failure of equipment or errors in ‘piloting’, according to the instructor list. The computer system also provides the operation of preventive or emergency pilot signalization units installed at the instrument panel or on cabin windshield. The simulated emergency situations can be accompanied by imitation of specific outer features, for example buffeting, shaking, and oscillations of angles of pitch, roll, etc.
However, the simulator allows carrying out training only on the basis of solutions of situational problems for the typical emergency situations.
In the real situation for cruise flight mode and during takeoff and landing, aircraft can experience an effect of significant aerodynamic forces and moments, which could cause the loss of their stability, for example while flying in aerodynamic jets of high level of turbulence generated by vortex generators moving near the aircraft, as well as by immobile vortex generators, which undergo the airflows of high level of turbulence and vorticity.
It is well known that flying aircraft generate the so called ‘wake vortices.’ The aircraft encounter with wake vortices generated by another object, for example by another aircraft, results in the substantial change of the angles of attack and sideslip. The aircraft experiences aerodynamic forces and moments that can throw it aside from the wake and while flying at low altitudes, for example, during takeoff and landing, can lead to hazard situations due to the impossibility of compensating such the effects by means of the aircraft controls.
The appearance of aircraft with wings of low aspect ratio and with high wing loading tends in the raise of wake vortex intensity increasing the hazard for aircraft entering the wake.
A lot of research work on transport and decay of vortices shows that the atmospheric factors such as wind, windshear, stratification, and turbulence play an important role in these processes.
There is a potential for optimizing the safe separations between aircraft during landing, takeoff and cruise flight on the basis of reliable forecasting of wake vortex dynamics with due regard for current weather conditions and now-casting and in-ground effect on wake vortex dynamics.
One of the main trends for decision of the problem of aircraft safe flight, when the determinant factor is wake vortices, is the selection of flight modes ensuring the required safety level. Therefore the great attention should be paid to pilot training in their estimation of different flight situations and decision-making for the corresponding flight maneuver.
Contrary to Russian flight safety systems oriented mainly to operations of pilots according to their personal analysis of the situation and flight conditions, the foreign flight safety systems are destined mainly for the use under the so called ‘Instrument Flight Rules’ when aircraft are controlled on the basis of flight controller commands implemented by pilots or in automatic mode. In such conditions it is appropriate to train pilots and controllers on the same situational tasks related with aircraft possible encounter with wake vortex danger areas in order to increase their skill in adequate evaluation of the situation and in seeking ways of preventing nonstandard situations.
The provision in simulator a possibility of simulation of most adequate wake vortex situations that may lead to flight incidents is the task of an utmost importance.
The goal of such training is to set a certain appearance of operational sequence for pilots or operators for different versions of visual and signal information provided to them; moreover the creation of experimental emotional and stress situation. The pilots or operators memorize the operational sequence appearance and fix their attention on their feeling.
However, as it is well known, that the decision-making in emergency situations is the most difficult operation in the operator activities. It consists of two stages: identification of the situation and determination of activity order to eliminate it. The operator, before proceeding any operation, should envisage his further steps. The perception of visual and voice signals in verbal form from a long-term memory, from indication means, or aurally needs a certain time under the time deficiency. The time for perception of graphic symbols is far less; and identification of the situation with the indication of the selected image zones permits to improve also the decision-making adequacy. Moreover, the effect of such physical factor as acceleration causes the detraction of pilot brain circulation, which may force even the short loss of consciousness under emotional and nervous tension. Therefore the provision of information necessary for decision-making to pilots or to flight controllers is preferable in graphical symbols before the actual decision-making time.